Process of cracking petroleum oil



Oct. 20, 1931.

Patented oct. 2o, i931 UNITED STATES PATENT oFFlcE GUSTAV EGLOFF, OF CHICAGO, ILLINOIS, ASSIGNORl TO UNIVERSAL OIL PRODUCTS COH- PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF SOUTH DAKOTA PROCESS OF CRACKVING PETROLEUM OIIi Application med December 14,1925, Serial No. 75,195. l:Renewed vAugust 12, 1930.

This invention relates to improvements in rocess of cracking petroleumv oil, and reers more particularly to the production of ethylene gas. By means of the resent invention, a substantial portion of t e petroleum oil is converted into olefine and more particularly, ethylene products. This is accom-` plished by iirst cracking the oil so as to produce a substantial percentage of cracked vapors, and thence passing said vapors preferably without cooling them, to a superheating zone Where they are further heated preferably under superatmospheric pressure, so as to further decom ose the vapors and form the desired quantities of the so-called fixed gases of the olene series, and more particularly the ethylene series.

In order to more readily understand the invention, I show the accompanying drawing, in which the apparatus is shown in a somewhat diagrammatic side l elevational view, and partly in vertical section, in which the invention may be carried out.

Referring now to the drawing, 1 des1gnates a furnace in which are positioned the burners 2 and the iue 3. In the furnace is mounted the still 4 which in the present instance, is shown as a shell, but may take the form of a coil and tank if desired. The shell is provided with the usual residuum drawoif, not shown, pressure gauge 5, thermostat 6, an insulated vapor pipe 7 having a throttle valve 8, which pipe leads to -an electric furnace 9 in which is positioned the pipe or coil 10, as may be desired. Of course, the superheating furnace does not need to be electrically heated, but may be theordinary furnace, if desired. The vapors pass out of the furnace 9 through the pipe 11 having throttle valve 12 into the condenser coil 13, thence through valve 14 to receiver 15 which receiver 15 is provided with liquid drawoff valve 16, gas outlet line 17, to which is connected the pipe 18, the gas meter 19 and a suitable gas holder 20.

The process may be carried out as follows: Mexican gas oil of 20.9 BaumeA may be heated in the still 4, while subjected to a pressure of sa 150 pounds, which pressure o may prevail t roughout the entire system,

to-wit: from the still 4 to and through the receiver 15. The distillation in the still 4 is continued until more than half of the oil passes out of the still inl the form of vapors, the temperature of the oil being from 800 to 850 F. more or less. AThe vapors ass through the pipe 7 into the furnace 9 w ere they were heated to a temperature from 1200 to 1300 F., where a large part of the vapors are broken down into fixed gases of the oleine series. The gas produced in one mstance, was 1110 cubic feet per barrel of oil treated. Of this 1110 cubic feet of gas, 21.89% by volume was olefine and 9.46% by volume, Was ethylene. The cubic' feet per barrel of ethylene produced was 105, and the pounds of ethylene per barrel (42) was 8.1

pounds.

In addition to the ethylene and-olene ser1es produced, propylene, butylene and amylenes were also produced.

The invention may be carried out having the system under uniform pressure, but a differentlal pressure may also be maintained on varlous parts of the system or the still alone may be maintained under pressure, while the superheating is maintained at atmospheric.

I claim as my invention:

1. A process for treating hydrocarbon oil to produce a product containing at least 15% hydrocarbons of the olene series comprising initially subjecting the liquid oil to pressure distillation so controlled as to yield cracked vapors representing an excess of 50% of the oil treated, subjecting the cracked vapors in a zone free from liquid or steam to a temperature in excess of 1200" F. While under superatmospheric pressure.

2. A process for treating hydrocarbon oil to produce a roduct containing hydrocarbons of the ole e series, comprising initially subjecting the 1i uid oil to ressure distillation so controlle as to iel cracked vapors representing in excess o 50% of the oil treated, and subjecting the cracked vapors in a 1.0 zone free from liquid or steam to a temperavture of at least 1200 F.

GUSTAV EGLOFF. 

